Visualization Analysis for the Influence of Molding Parameters on the Characteristics of Trapped Gas in Injection Molding

doi:10.3901/JME.2017.18.049

Abstract

Abstract: Trapped gas phenomenon is one of the key factors that restrict the performance of the workpiece produced by injection molding. The injection molding process of ring parts with lug boss is taken as the research object. The influence of molding parameters (melt temperature, mold temperature) on the mechanism of trapped gas is explored by directly observing the dynamic process of gas trapped in the melt filling process with the visualization device. The experimental results show that increase of the injection speed can reduce the trapped gas area and the distance of the trapped gas in the certain range of mold temperature and melt temperature. In the case of low injection speed, improving the melt temperature or mold temperature can reduce the trapped gas area and the distance of the trapped gas. Under high injection speed, the area of the trapped gas and the distance of the trapped gas increased firstly and then decreased with the increasing of the melt temperature. The area of the trapped gas increased with the increasing of the mold temperature.

Key words: injection molding, trapped gas phenomenon, visualization

CLC Number:

TQ320

LU Yong, JIANG Kaiyu, ZUO Junchao, WANG Minjie. Visualization Analysis for the Influence of Molding Parameters on the Characteristics of Trapped Gas in Injection Molding[J]. Journal of Mechanical Engineering, 2017, 53(18): 49-56.

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